This will reject emails containing the following attachments

/^sContent-(Disposition|Type).names=s"?(.+.(ad[ep]|asd|ba[st]|bhx|b64|c[ho]m|cmd|cpl|crt|dbx|dll|exe|hlp|hqx|hta|in[fs]|isp|js|jse|lnk|ocx|md[etw]|mim|ms[cipt]|nws|ocx|ops|pcd|pi|pif|prf|reg|scf|scr|sct|sh[bms]|swf|uu|uue|vb|vb[esx]|vxd|wab|ws[cfh]))"?s*$/ REJECT FOR SECURITY REASONS, ".$3" FILETYPES ARE AUTOMATICALLY REJECTED BY THIS SERVER, "$2" WAS REJECTED AS IT MAY CONTAIN VIRUSES